There seem to exist several grub2 versions trashing
boot_params.hdr.acpi_rsdp_addr.
So don't just believe this address to be valid, but verify it pointing
to a valid RSDP table.
Signed-off-by: Juergen Gross <jgr...@suse.com>
---
To be applied on top of my RSDP series currently in tip.git x86/boot
Mike Galbraith has tested this patch to repair his broken boot
---
drivers/acpi/acpica/tbxfroot.c | 36 ++++++++++++++++++++++++++++++++++++
drivers/acpi/osl.c | 2 +-
include/acpi/acpixf.h | 5 +++++
3 files changed, 42 insertions(+), 1 deletion(-)
diff --git a/drivers/acpi/acpica/tbxfroot.c b/drivers/acpi/acpica/tbxfroot.c
index f9f9a7da2cad..9edc71780a38 100644
--- a/drivers/acpi/acpica/tbxfroot.c
+++ b/drivers/acpi/acpica/tbxfroot.c
@@ -249,6 +249,42 @@ ACPI_EXPORT_SYMBOL_INIT(acpi_find_root_pointer)
/*******************************************************************************
*
+ * FUNCTION: acpi_verify_root_pointer
+ *
+ *
+ * PARAMETERS: rsdp_address - Pointer to suspected RSDP
+ *
+ * RETURN: AE_OK if rsdp_address really points to a RSDP, AE_NOT_FOUND
+ * else
+ *
+ * DESCRIPTION: Verify a physical address being a valid RSDP
+ *
+
******************************************************************************/
+
+acpi_status ACPI_INIT_FUNCTION
+acpi_verify_root_pointer(acpi_physical_address rsdp_address)
+{
+ acpi_status status;
+ struct acpi_table_rsdp *rsdp;
+
+ ACPI_FUNCTION_TRACE(acpi_verify_root_pointer);
+
+ rsdp = acpi_os_map_memory(rsdp_address, sizeof(*rsdp));
+
+ if (!rsdp)
+ return_ACPI_STATUS(AE_NO_MEMORY);
+
+ status = acpi_tb_validate_rsdp(rsdp);
+
+ acpi_os_unmap_memory(rsdp, sizeof(*rsdp));
+
+ return_ACPI_STATUS(status);
+}
+
+ACPI_EXPORT_SYMBOL_INIT(acpi_verify_root_pointer)
+
+/*******************************************************************************
+ *
* FUNCTION: acpi_tb_scan_memory_for_rsdp
*
* PARAMETERS: start_address - Starting pointer for search
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 2b77db914752..facff5c11f32 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -201,7 +201,7 @@ acpi_physical_address __init acpi_os_get_root_pointer(void)
return acpi_rsdp;
#endif
pa = acpi_arch_get_root_pointer();
- if (pa)
+ if (pa && acpi_verify_root_pointer(pa) == AE_OK)
return pa;
if (efi_enabled(EFI_CONFIG_TABLES)) {
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index e1dd1a8d42b6..1edc47bd13c1 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -505,6 +505,11 @@ ACPI_EXTERNAL_RETURN_STATUS(acpi_status ACPI_INIT_FUNCTION
ACPI_EXTERNAL_RETURN_STATUS(acpi_status ACPI_INIT_FUNCTION
acpi_find_root_pointer(acpi_physical_address
*rsdp_address))
+
+ACPI_EXTERNAL_RETURN_OK(acpi_status ACPI_INIT_FUNCTION
+ acpi_verify_root_pointer(acpi_physical_address
+ rsdp_address))
+
ACPI_EXTERNAL_RETURN_STATUS(acpi_status
acpi_get_table_header(acpi_string signature,
u32 instance,
--
2.13.6
